Decision making associated with chemically contaminated waste sites is generally based on 1) contaminant bioavailability to potentially exposed populations and 2) the toxicity and biological persistence of the contaminants present. Wildlife inhabiting contaminated sites are front line indicators of chemical bioavailability due to their intimate association with the site and subsequent expression of exposure and effects-associated biomarker responses. Characterization of dose-response relationships have shown that wildlife species are often, in fact, more sensitive than standard laboratory species in their response to waste site contaminants. Research within this project will continue to focus on the characterization and application of biomarker technologies in wildlife populations inhabiting hazardous waste sites. Biomarkers developed in the Project will be applied at Three National Priorities List sites, The Rocky Mountain Arsenal, Sangamo Westin Associated PCB dump sites and a waste metals, oil and PCB site . The biomarkers applied to wildlife on these sites will encompass both established (i.e., reproductive success, cytochrome P-450 activities, cellular and humoral immune function, porphyrin profiles and H4IIE/dioxin equivalency assays) and nw approaches. In vivo and in vitro estrogenicity and antiestrogenicity techniques will be developed for use on organochlorine pesticide and halogenated aromatic hydrocarbon contaminated sites. Chelator-induced excretory depuration of heavy metals will be combined with porphyrin profile analysis to strengthen heavy metal exposure assessments. cDNA probes for cytochrome P-450 subtypes will be used to determine forms and transcription rates of inducible genes both constitutively and following xenobiotic induction. Changes in muscarinic acetylcholine receptor site and sub-type densities in response to sub-lethal organophosphate insecticide exposure in starling nestlings will be evaluted in terms of post-fledging survival of the nestlings. Immune function assays will be modified and optimized to make them field deployable and less dependent on laboratory intensive techniques. Species studies will be the deer mouse (Peromyscus maniculatus). the European starling (Sturnus vulgarus) and endemic species encompassing site-specific wildlife populations. Biomarker techniques and alterations in contaminant metabolite profiles will be used to access contaminated field sites and their responses will be used as proposed criteria in remediation site and contaminant prioritization decisions and remediation success assessments. Project 7 investigates and applies biomarker techniques to wildlife species inhabiting waste sites in order to evaluation contaminant bioavailability and effects for use in remediation prioritization and success evaluations. This area of research is relevant to the theme of the Program Project because it integrates and applies health effects biomarker techniques, developed by this and associated projects, into the prioritization and success evaluation processes critical to site remediation.